(1) A power conferred to enter premises, or to take action on premises, may
not be exercised unless the person proposing to exercise the power is in
possession of an authority and produces the authority if required to do so by
the owner or occupier of the premises.
(2) The authority must be a written
authority that--
(a) states that it is issued under this Act, and
(b) gives
the name of the person to whom it is issued, and
(c) describes the nature of
the powers conferred and the source of the powers, and
(d) states the date
(if any) on which it expires, and
(e) describes the kind of premises to which
the power extends, and
(3)
However, a police officer exercising a power to enter premises, or to take
action on premises, must produce his or her warrant card if required to do so
by the owner or occupier of the premises in lieu of an authority (unless the
police officer is in uniform).